(1) Field of the Invention
The present invention relates to a busbar molded article including a busbar stamped out from an electrically conductive substrate in a specific circuit pattern and an electrically conductive substrate formed in one piece with the busbar, and to a process for manufacturing the busbar molded article. The present invention also relates to an electronic unit having the busbar molded article, which electronic unit controls an auxiliary machine of a motor vehicle such as a wiper, washer, front light, foglamp and air-conditioner.
(2) Description of the Related Art
An example of such a conventional busbar molded article and a conventional process for manufacturing the busbar molded article is shown in FIGS. 5–7 (Japanese Patent Application Laid-Open No. 2000-77152 and Japanese Patent Application Laid-Open No. 2001-251729).
A conventional example (Japanese Patent Application Laid-Open No. 2000-77152) shown in FIG. 5 relates to a method, in which a pair of grippers 52, 53 that hold a terminal part 50 is rotated by a specific angle so as to be bent as a plurality of the terminal parts 50 received in a connector housing (not shown in the figure) abut against a terminal pedestal 51.
A conventional example (Japanese Patent Application Laid-Open No. 2001-251729) shown in FIG. 6 relates to a terminal part 55 of a busbar 54 to be received in an electric junction box, in which the terminal part 55 is bent by an angle of 90° and twisted so as to be received into a female terminal of the other side, thereby the terminal part 55 faces in the same direction as the female terminal faces, so that the terminal connection can be carried out without putting an intermediate terminal therebetween.
A conventional example shown in FIGS. 7A and 7B relates to a busbar molded article 60 having a plurality of terminal parts 62 for connecting to a substrate, in which the base-side of the terminal part 62 is bent by stamping with a pressing machine so as to form the terminal part 62 L-shaped at an end of a busbar 61. FIG. 7A shows a state before the stamping, in which the terminal part 62, extending straightly on a condition of being stamped out from the conductive substrate, is placed between a lower mold 64 having a L-shaped notch 64a and an upper mold 63 that enters into the notch 64a. As shown in FIG. 7B, when the upper mold 63 is brought down to the fixed lower mold 64, the base-side of the terminal part 62 is stamped being put between the upper and lower molds 63, 64 so as to be bent into a L-shape corresponding to the notch 64a of the lower mold 64.
The terminal part 62 is provided with a resin band 65 for correcting the alignment formed in one piece therewith. Accordingly, after the terminal part 62 is bent, a table 66 on which the busbar molded article 60 is placed is shifted to this side so that the resin band 65 slides along a groove 63a of the upper mold 63, thereby the busbar molded article 60 is removed from the pressing machine.
As a further conventional example, in Japanese Patent Application Laid-Open No. 2001-339825, it is described that a conductive substrate is subjected to stamping and bending so as to form a tab-shaped terminal part.
However, as for the conventional examples described above, the following problems exist. In the first conventional example, the terminal part 50 is nipped by a pair of the grippers 52, 53 and bent by rotating the grippers 52, 53 by a specific angle. Therefore, when a plurality of the terminal parts 50 arranged in a row laterally are simultaneously bent, a precise bending of the terminal parts might not be carried out due to a problem of the stiffness of the bending machine. Further, since the bending method of the terminal parts 50 is complicated, the method is not suitable to automation having a problem of efficiency.
In the second conventional example, although the terminal part 55 can be bent with a simple method by using a twisting jig, a plurality of the terminal parts 55 cannot be simultaneously bent, causing low efficiency being not suitable for mass production. A precise bending of the terminal parts 55 might not be carried out with good reproducibility.
In the third conventional example, since a plurality of the terminal parts 62 are nipped between the upper and lower molds 63, 64 of the pressing machine and subjected to stamping, the terminal parts 62 may be bent efficiently precisely. However, since a plurality of the terminal parts 62 are provided with the resin band 65 for correcting the alignment, therefore when the mold 63 is lifted to return it to the original position, the mold 63 might interfere with the resin band 65 (i.e. a problem of undercutting). Accordingly, when the bent busbar molded article 60 is to be removed from the pressing machine, the table 66 on which the busbar molded article 60 is placed must be slid in a direction crossing at right angles with the acting direction of the mold 63, causing an excessive man-hour for the manufacture.
Moreover, when an obstacle such as a rising terminal part or projection exists in the direction in which the table 66 is slid, the table 66 cannot be slid in the direction crossing at right angles with the acting direction of the mold 63 after the terminal part 62 is bent, causing a problem that the busbar molded article 60 cannot be removed from the pressing machine after the bending.
In the fourth conventional example, since a method of bending simultaneously a plurality of the terminal parts arranged in a line is not provided, therefore there is a problem that the efficiency of the bending is low.